Modification by antiplatelet drugs of acute EEG changes induced in the rat by sodium arachidonate

It can be readily shown in vitro that various compounds inhibit platelet aggregation but it has been difficult to demonstrate in vivo. A method is suggested here to enable in vivo testing of these compounds; the method utilizes relatively low doses of sodium arachidonate, made possible by the ligation of the pterygopalatine artery. Adenosine, ATP and sulfinpyrazone, agents known to inhibit platelet aggregation in vitro, were effective in varying degrees in inhibiting in vivo platelet aggregating response as suggested by their ability to antagonize arachidonate-induced EEG depression.